• TorrentXTorrentX December 2016
    So I'm working on a thermal cycler. And I'm looking to source a heatblock for the tubes. I haven't been able to find a good one for less than $100 most run higher, and I don't want to use a home-made cludgy one with a dremmel as that would be unlikely to produce reliable, repeatable results. So this leads me to a few questions.

    1.) Am I missing something?  Is there a place to purchase cheap heat-blocks for .2ml eppendorf tubes?  Or an alternative solution.
    2.) What have others that ran into the problem done? Just ponied up for the expensive heatblock or tinkered with a homemade one til it worked?
    3.) If there's no good answer to the first two questions, is this something that the community would find valuable if I worked on a solution for?
  • UsefulIdiotUsefulIdiot December 2016
    When you say heat block, what do you mean? Is it just like a holder for test tubes that get heated evenly? From what I found online, it seems to be a solid metal block, unless I am missing something. If it is solid metal, then get appropriate measurements from the tubes tubes and use CAD to model it out. Once you finish with that, find a precision machining tool like a C&C machine in your area, or look on the internet for a site that will make the part for you. I unfortunately have no site suggestions at the moment. Shapeways may be worth a look, but their aluminum is only about 85% purity, and their margin of printer error is +/- 0.2 mm, at least according to their website page on aluminum, so that may lead to variability in results. Of course, from what I know of PCR (not much), you only need to hit and hold the target temperatures for a short while for it all to work, which makes it seem like the heat block is less of a precision tool and more of a convenience for even heating, but again, I don't know too much about the process other than the basics.

    Good luck on your thermal cycler.
  • ThomasEgiThomasEgi December 2016
    as for PCR cycling you have two commonly found options.

    1.  Putting your test tubes into a block of milled aluminum and heat/cool the block. you'd need a heating cartridge and/or a colling element (probably peltier). You'd also need a temperature sensor and a controller to properly drive your heating/cooling system. Commonly done, cool project if you'r into electronics and machining and stuff.

    2. you simply close the test tubes and put them in water bathes with appropriate temperatures. You need like 3 different tubs of water but that.

    Milling a block of aluminum is a pretty easy task if you have someone with a CNC mill. Most tooling shops should be able to get that done easily. Even most hobbyists should be able to pull it off.
  • chironexchironex December 2016
    If you haven't already seen this, this may be of use. A lightbulb/pvc pcr that works pretty well all things considered LINK
  • TorrentXTorrentX January 3
    The lightbulb PCR is pretty cool.  That's a good idea, I'll have to look into that or a similar air heat/cool to see if it can be as effective as an thermoelectric cooler. 

    I've got someone who can mill and shape the aluminum for the most part, but to bore the tapered wells to a tolerance of 180µm needs a custom bit. (Been looking at sourcing them, but haven't gotten good responses yet). I'll do some research into what the actual heat accuracy needs to be.  But I was hoping to be in the range of the OpenPCR project.  

    I was planning on using a Peltier device, for heating and cooling. 

    Basically, my current goal is to approach the mechanical level of the OpenPCR project while being able to source the individual parts easily.  And at a MUCH cheaper price. 
  • glimsglims January 4
    I like the concept of open pcr and maker ethic and all that. But it's 650 for basically a knock off. Your bacteria don't care about the hacker ethos. 

    Ebay has pcr machines for like, 150 dollars. I know that you said you're having problems finding one for under 100 and thats true, they aren't that cheap... But since a brand new one can cost up on 15k, suddenly, 150-200 bucks just doesn't sound that bad. I'm in brazil now and their version of ebay has the pcrs at roughly the same price.

    I know that http://www.the-odin.com/ was selling refurbished pcr machines cheap as well.

    Of course, if your goal is actually making this thing as opposed to doing gene work, then it sounds like you're on the right track.

  • TorrentXTorrentX January 4
    Oh wow! I didn't realize they had come down in price so much on EBay.  

    I'd still like to make one and source and document it for others, but at those prices I can go ahead and get started with splicing AND have a working base model to compare against mine against.  Thanks @glims!
  • misslittymisslitty January 8
    A little off topic but do any if you have experience with LAMP?
  • BirdMachineBirdMachine January 10
    LAMP as in a Linux Apache Mysql PHP server? I do :) If that's what you're looking for feel free to PM me.

    And huh, that odin link has a pretty inexpensive looking bacteria CRISPR kit. Might be a nice place to get my toes wet with the more 'bio' side of things!
  • misslittymisslitty January 10
    I actually meant loop-mediated isothermal amplification, but I appreciate it regardless!
  • glimsglims January 11
    What's the question, @misslitty?

  • misslittymisslitty January 11
    Wondering if anyone has had luck using LAMP for diagnostic purposes instead of PCR.
  • glimsglims January 13
    boop

    https://malariajournal.biomedcentral.com/articles/10.1186/s12936-015-0573-y

    I myself haven't done this, but it makes sense.

  • decaldecal January 14
    @TorrentX You might want to ask Tito Jankowski of Impossible Labs cause the original balsa wood OpenPCR came packaged with one.. Another person you may want to check with would be the sysadmin of the-odin.com. 

    @misslitty I saw where some biotech companies have already begun marketing LAMP and RT-LAMP solutions to hospitals as a speedy detection mechanism and front line of defense for infectious diseases.  It's a win-win for the emergency room staffers since they get the results right away (no need to wait for test results to come back from the lab with the new devices/kits that are being manufactured.)  Rapid response obviously leads to swifter quarantine as well.

    I'm sure segments of the military/industrial complex in Langley have interest in it for biochemical weapons and bioterrorism purposes.  Too bad most of their research is classified.  Linking to one of the commercial solutions..